/Engine/Source/Runtime/ApplicationCore/Public/GenericPlatform/Accessibility/GenericAccessibleInterfaces.h
Retrieve the native OS window backing this accessible window. This can be safely casted if you know what OS you're in (ie FWindowsWindows on Windows platform).
The native window causing this accessible window to exist
[TSharedPtr](API\Runtime\Core\Templates\TSharedPtr)< [FGenericWindow](API\Runtime\ApplicationCore\GenericPlatform\FGenericWindow) > GetNativeWindow() const